The Soft button of the light control
board works only if the light is of a Spot type since it is closely
linked to dropped shadows.

A succession of examples will help much
better than a long and annoying text to understand how it works.

The Soft function mimics the penumbra
fringe effect which borders the dropped shadow when it is produced by a
luminous surface (in english it is often mentioned as Area Light,
surface of lights). the bigger the lighting surface is , the
bigger the penumbra area is.

The Soft button allows to choose
values between 0.01 et 100.Used with the Bias button it allows
to refine the realism of the shadows.